UART DMA circular buffer

Example description

This example setup the UART and DMA into receive with a circular buffer. This allows to set a very loose real time constraint for the reception of non flow controlled UART messages.

For this example we will need a data feed to connect to the Smarbond device. We will illustrate this example with an ADAFRUIT ULTIMATE GPS BREAKOUT. This board is 3.3V and the GPS device will start to send ASCII character on the TX pin as soon as it is powered up. Any 3.3V UART emitting device can be used.

HW and SW configuration

  • Hardware configuration

    • This example runs on The DA14681/DA14683 Bluetooth Smart SoC devices.
    • The USB Development kit is needed for this example.
    • Connect the USB Development kit to the host computer.

  • Software configuration

    • This example requires:
    • Smartsnippets Studio 1.6.3.
    • SDK1.0.12
    • SEGGER’s J-Link tools should be downloaded and installed.

How to run the example

Initial Setup

  • Connect the ULTIMATE GPS BREAKOUT to the Smartbond device following This schematic

schematic

  • compile the code and load it (RAM or QSPI), run it.
  • Open the virtual COM port of the USB Dev kit (in this case COM93 115.2kbps)

schematic

The terminal displays the GPS data messages.

Known Limitations

  • There are No known limitations for this example. But you can check and refer to the following application note for known hardware limitations.
  • Dialog Software [Forum link](https://support.dialog-semiconductor.com/forums/dialog-smartbond-bluetooth-low-energy-%E2%80%93-software”Forum link”).
  • you can Refer also for the Troubleshooting section in the DA1585x Getting Started with the Development Kit UM-B-049.

License

Copyright (c) 2018 Dialog Semiconductor. All rights reserved.

This software (“Software”) is owned by Dialog Semiconductor. By using this Software you agree that Dialog Semiconductor retains all intellectual property and proprietary rights in and to this Software and any use, reproduction, disclosure or distribution of the Software without express written permission or a license agreement from Dialog Semiconductor is strictly prohibited. This Software is solely for use on or in conjunction with Dialog Semiconductor products.

EXCEPT AS OTHERWISE PROVIDED IN A LICENSE AGREEMENT BETWEEN THE PARTIES OR AS REQUIRED BY LAW, THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. EXCEPT AS OTHERWISE PROVIDED IN A LICENSE AGREEMENT BETWEEN THE PARTIES OR BY LAW, IN NO EVENT SHALL DIALOG SEMICONDUCTOR BE LIABLE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THE SOFTWARE.